CBOM Pre-conference Session - OEMACoemac.org/download/2014-Sunday/Doug Hamm_OEMAC Conference 2014_CBOM.pdf · PAIN and FITNESS TO WORK EVALUATION • Describes daily low back pain

CBOM Pre-conference Session

PAIN and FITNESS TO WORK EVALUATION

Statement of Disclosure:

Nothing to Disclose

Statement of Disclosure:

Nothing to Disclose


Assessing Pain and

Fitness to Work

Ever felt like this

about it?


Case Scenario

• A 43 year old Caucasian male sees you in your office

• Tells you of a history of persisting low back pain for the past 20 years

• At age 27 has his first lumbar surgery but back pain persists

• At age 37 has lumbosacral fusion procedure but complications

• Has 2 further lumbar procedures at age 38

• After failed back surgery gets spray and stretch and trigger point

injections over the past five years, sometimes uses crutches

Cont.


• Describes daily low back pain “like a toothache” with exacerbations from

minor back motions and “stress”

• Currently has a high profile administrative job, attendance is OK but he

hides his condition well, looks fit

• Wants to apply for the job as CEO of a large corporation with vast

international interests

• Job is high pressured, multi-tasking, executive demands, with some safety

sensitive aspects

• Is he fit to work as a CEO?


Case Scenario cont.

• He campaigns and wins the 1960 Presidential election

• Has ongoing back pain

• (Has a nastly flare up after planting a tree in Canada in 1961)

• His physician, Dr. Janet Travell, (of Travell & Simons’ textbook

“Myofascial Pain and Dysfunction - Trigger Point Manual”) gives him

procaine injections 2-3 times/day

• He takes up to 5 hot showers a day for his back

• Maintains a public image of fitness and vitality despite his back pain and

other longstanding health issues


• He tries to use crutches out of the

public’s view

• But he doesn’t miss any of his 1036

days on the job due to his back

problem

• Was wearing his back brace on the

day of his assassination, Nov. 22,

1963 (so he couldn’t slump forward

enough after the first bullet to his

upper back to avoid the next bullet

to the back of his head?)

R. S. Pinals and A. L. Hassett, “Reconceptualizing John F. Kennedy’s chronic

low back pain” Regional Aesthesia and Pain Medicine 38 (2013): 442-446.

Pain is

• A universal experience but

• Difficult to communicate

“The pain of another is ultimately unknowable”

- James D. Katz in Maldynia, CRC Press, 2013:26

• Socially and psychologically constructed

• A highly individualized experience

• Difficult to measure


(Another politician in pain!)


Pain was understood in classical times as an

emotion rather than as a sensation (“affect theory

of pain”)

Into the middle ages pain was viewed as an

internal imbalance or an inner disorder of the

bodily states

e.g.

• imbalance of the 4 bodily humors

• a distortion of inner stasis or body fibres

• animal vs. vegetative conditions (vitalists)

• conflict of body and the soul (animists)

• etc.

The current neurosensory view of pain is novel


René Descartes (1596-1650) brings

about the age of the sensory model of

pain and the so-called “specificity

theory of pain”, i.e. pain is a specific

sensation with its own sensory

apparatus.

The modern era of pain

Cartesian model of pain transmission

- Particle of heat activates surface spot

tethered to the brain by a fibre which

opens a valve releasing animal spirits

activating the motor functions


Johannes Müller’s research into

sensory nerves gives a biological basis

for Descartes’ model of pain

transmission.

Our sensations are determined by

receptors linked to cortical centres by

sensory nerves. So, as our sensations

are determined peripherally so also is

our pain?

Johannes Peter Müller (1801-1858)


Müller’s student Emil du Bois-Reymond

(1818-1896) discovers the action potential

in 1865

Peripheral receptors determine sensory

outcomes

He even claims that if the auditory nerve

was somehow connected to the visual

cortex and the optic nerve to the auditory

cortex we could see thunder and hear

lightning!


Cambridge neurophysiologist Charles

Sherrington (1857-1952) develops

the understanding of the reflex arc

and coins the term “synapse”.

He concludes that surface receptors

determine the excitability threshold

for the somatic senses and proposes

the idea of a “nociceptor”.

Sherrington shares his 1932 Nobel

Prize with the electrophysiologist

Edgar Adrian who discovers slow and

fast pain fibres.

The biological “wiring” is now in

place for the Cartesian specificity

theory.

Charles Sherrington


From Kandel and Schwartz , Principles of Neural Science, 5th ed. 2013: 534.


Pain as nociception is disturbed by Melzack and Wall

Patrick Wall (1925-2001)Ronald Melzack (1929-)

“It was fifty years ago today… “ ♬♪♫


Melzack and Wall’s ground-breaking “gate control” model of pain

published in Science, 1965:

Ascending

Spinal Tracts

to Brain

Dorsal

Horn of

Spinal

Cord


• Mechanoreceptor afferents inhibit (close) the pain pathway gate whereas C afferents activate (open) the pain gate.

• Moreover, activity from descending fibers can also modulate the gate.

• We now know that pain pathway modulation occurs at many supraspinal relay centres


Beyond Nociception: What about “functional overlay1” in pain?

1See W. Bromberg, “Functional Overlay: An Illegitimate Diagnosis” Western Journal of Medicine 130 (1979):561-565.

From Melzack

and Wall, The

Challenge of Pain

2nd ed. revised

1996, page 162


In 1968, Melzack and Casey challenged the dichotomous understanding of

pain and affect, i.e. that nociception and affect are parallel or sequential:

Cognitive-evaluative: appraisal from psychosocial contexts and beliefs

Motivational-affective: emotional, aversive, and avoidant aspects of pain

Sensory-discriminative: intensity, location, quality, and duration


Just remember ACS:

The International Association for the Study of Pain (IASP) has based

its definition of pain on this multidimensional model :

“Pain is an unpleasant sensory and emotional experience associated

with actual or potential tissue damage, or described in terms of such

damage.”


McGill Pain

Questionnaire


Sensory-discriminative aspects of the pain experience

• Location

Pain site checklists and drawings, (have them point to it!)

• Onset and course to date (triggers and relievers)

• Frequency, duration, migration, radiation, fluctuation, etc.

• Quality

burning, stabbing, aching, throbbing, shooting, piercing,

pounding, pulsing, gnawing, crushing, heavy, pulling,

searing, sharp, dull, deep, stinging, etc. (See MPQ)

• Intensity

Verbal Rating Scales (VRS), Visual Analog Scales (VAS),

Numerical Rating Scales (NRS)


“Somatoform-functional pain is typically associated with symmetric patterns, long

lines, and a higher number of marks.” Egloff et al. BMC Musculoskeletal Disorders

13 (December 20, 2012): 257.

What About

Pain

Drawings?


Caution:

A meta-analysis of pain drawings to identify or predict

psychological state concluded that “pain drawings do not predict

psychologic state at a level that is acceptable for clinical use”

Carnes, Ashby and Underwood, Clinical Journal of Pain 22 (June

2006): 449-457.

What about pain rating scales?


We physicians love numerical ratings of pain, but

what do numerical ratings really represent?

(from Stevens, Carton, and Shickman, 1958)

Is the perception of pain a power function of the stimulus intensity?

(from Tursky, Jamner, Friedman, 1982)



What about this pain response to a standardized stimulus?

Study of reported pain intensity after a standardized SC injection of

1% lidocaine in 165 patients with chronic pain (Manabat et al., 2011)


Conclusion:

Numerical pain scales cannot be readily compared between subjects

Numerical pain scales are not predictive of disability but are useful for

estimating within subject variation in pain, e.g. responses to

aggravating factors or pain relieving factors, time trends, medications,

and other treatment effects.

(Myles et al.,

Anesthesia and

Analgesia 89 (1999):

1517-1520)


36 year old female RCMP officer who was T-boned while

driving home from her work as a patrol officer and developed

chronic shoulder and low back pain.


10 Worst imaginable pain. Causes you to be completely

incapacitated and barely able to talk. Requires

immediate emergency hospitalization.

8-9 Pain that causes disability between levels 7 and 10.

Nearing need for hospitalization.

7 Severely disabling pain. You cannot use or move the

painful area. You have difficulty talking and

concentrating on anything but the pain. Needing to lie

down and/or pain-related tearfulness are also

common.

6 Pain that causes disability between levels 5 and 7.

5 Very disabling pain. Causes great difficulty moving or

applying any strength through the painful area. You

are unable to complete the current activity.

4 Pain that causes disability between levels 3 and 5.

3 Functionally disabling pain. Pain that is starting to

affect your ability to perform the current activity (for

example decreased movement, decreased speed,

and/or the need to briefly rest and/or stretch in order

to continue completing the current activity).

0.25-

2.75 Non-disabling pain. The pain is present, but not yet at

a level which limits you from performing the current

activity.

0 No pain or discomfort.

Critical to standardize numerical scales


“The results suggest that baseline physical

functioning and overall mental and physical

health status are more predictive of specific

patterns of post-injury employment than

pain intensity measures, possibly because

there is considerable idiosyncratic variation

in the pain intensity measures.”

Marjorie L. Baldwin, Richard J. Butler, William G. Johnson,

“Self-reported Severity Measures as Predictors of Return-

to-work Outcomes in Occupational Back Pain” Pierre Côté,

Journal of Occupational Rehabilitation 17 (2007): 683-700.




Fluctuations / Patterns of pain (Exacerbating /Alleviating factors)

What is the effect of:

• ambient heat and cold

• dampness/humidity

• weather changes

• body and limb movements

• rest

• postures, e.g. driving, computers

• stress

• fatigue

• alcohol, coffee, smoking (tobacco, marihuana, OTC/Rx and OTC

medications, etc.)

• inactivity

• sleep

• recreational activities (gardening, crafts, hobbies, etc.)

• domestic activities (housekeeping, shopping, childcare, etc.)


Effects of treatments (conventional and others) on pain

• Macrobiotics or Megavitamins

• Special Diets or Nutritional Supplements

• Special Changes in Lifestyle

• Relaxation / Biofeedback Techniques

• Hypnotherapy

• Yoga/Meditation

• Counseling or Prayer Therapies

• Acupuncture or Acupressure

• Traditional Ethnic Medicine treatments e.g. Chinese, Ayuraveda,

• Homeopathic Medicine / Naturopathy

• Herbal Medicine

• Rolfing

• Reflexology

• Aromatherapy

• Craniosacral Therapy

• Chelation Therapy

• Colonic Enemas

(Electro)magnetic / pulsed fields, wearables, mattress pads, etc.

• Electrostimulators


Motivational-affective aspects of the pain experience

• Motivation-Affect is even more challenging to measure than pain

intensity.

• The underlying mechanisms are even less defined.

• There is confounding in measurement by pain intensity and quality

• Measurement tools are less validated

• Several of the verbal clusters on the McGill Pain Questionnaire (i.e.

groups 11-15) address the affective aspect.

• Consider asking “where is your most bothersome pain” (it isn’t always

the one that is most intense) and “what is most bothersome about your

pain”?


Screening questionnaires shouldn’t be relied upon for definitive

definitions, diagnoses, or prognoses. Like functional testing they offer

another “window” into the pain experience.

Time to complete Reliability Validity

Patient Health Questionnaire - 9

PHQ-9 3 min. ++ ++

Beck Depression Inventory second ed.

BDI-II 5-10 min. + ++

Quick Inventory of Depressive Symptomatology

QIDS

5-10 min. + ++

Hamilton Rating Scale for Depression

HAMD 15-30 min. + ++

Montgomery–Asberg Depression Rating

MADRS 15 min. ++ ++

T.A. Furukawa, “Assessment of Mood: Guides for Clinicians”

Journal of Psychosomatic Research 68 (2010): 581-589.


Measure

Description

Scoring

PRIME-MD Predecessor of PHQ, now mainly of historical interest.

(PRIMary care Evaluation of Mental Disorders)

Combined self-administered patient screener with clinician follow up questions

PHQ Five modules covering 5 common types of mental disorders: depression, anxiety, somatoform, alcohol, and eating

Selected provisional DSM-IV diagnoses for all types of disorders except somatoform.

PHQ-9 Depression scale from PHQ. Nine items, each of which is scored 0 to 3.

GAD-7 Anxiety measure developed after PHQ but incorporated into PHQ-SADS.

Seven items, each of which is scored 0 to 3, providing a 0 to 21 severity score.

PHQ-15 Somatic symptom scale from PHQ. Fifteen items, each of which is scored 0 to 2, providing a 0 to 30 severity score.

PHQ-SADS PHQ-9, GAD-7, and PHQ-15 plus panic measure from original PHQ.

See scoring for these scales above.


During the past 4 weeks, how much have you been

bothered by any of the following problems?

PHQ-15


Lars de Vroege et al., Validation of the PHQ-15 for Somatoform Disorder in the Occupational Health Care Setting” Journal of Occupational Rehabilitation 22 (2012): 51-58.

PHQ scores ≥

6 7 8 9 10 11

Sensitivity 82.6

69.6 60.9 56.5 52.2 39.1

Specificity 34.5

46.4 54.8 61.9 70.2 78.6

Negative Predictive Value 25.7

26.2 26.9 28.9 32.4 33.3

Positive Predictive Value 87.9

84.8 83.6 83.9 84.3 82.5

In this study of employees sick listed for more than 6 months, the authors

state that “If the optimal balance between sensitivity and specificity is

sought, a cut point of 9 yields sensitivity of 56.5% and specificity of 61.9%...

The findings suggest that the PHQ-15 may be used as a screener in the OH

setting, in order to alert the OHP of the possibility of somatoform

disorders.”?


C. Bass and P. Halligan, “Factitious Disorders and Malingering: Challenges for Clinical

Assessment and Management” The Lancet 383 (April 19, 2014): 1422-1432.

What about symptom

“exaggeration” or

“magnification”?

(“functional overlay”!)


The challenge of the so-called

“non-organic findings” in pain

Waddell’s Signs were first proposed in

1980 by Gordon Waddell from studies of

“problem back patients” in Glascow and

Toronto. He identified 5 categories which

suggested more “detailed psychosocial

assessment” in chronic low back pain. He

found that 3 such signs were present in

29% of “problem backs”.


Waddell’s “Nonorganic Signs”

1. Tenderness

Superficial skin tender to light touch

Nonanatomic deep tenderness not localized to one area

2. Simulation

Axial loading pressure on the skull of a standing patient

induces lower back pain

Rotation: shoulders and pelvis rotated in same plane induces

pain

3. Distraction

Difference in straight leg raising in supine and sitting positions

4. Regional

Weakness: many muscle groups, “give-away weakness”

(patient does not give full effort on minor muscle testing)

Sensory: sensory loss in a stocking or glove distribution,

non-dermatomal

5. Overreaction

Disproportionate pain behavior e.g., facial or verbal

expressions, guarding, etc.


“Waddell’s Signs” have been much misused leading to Waddell to

note a number of caveats in an article in Spine in 1998. According to

Waddell, behavioral responses to examination (i.e. Waddell’s

Signs”)

• Cannot be assumed to be deliberately simulated (“faked”)

• May be behavioral signs of fear responses

• Must be considered in context of patient’s illness/injury beliefs

• May have associated comorbidities

• Show inter-rater variability

• Are not a psychological assessment

• Do not rule out significant organic disorder

• Do not determine “functional overlay” or exaggeration

• Are not a test of credibility or veracity

Chris J Main and Gordon Waddell, Behavioral Responses to

Examination: A Reappraisal of the Interpretation of “Nonorganic

Signs”” Spine 23 (1998): 2367-2371.


http://www.youtube.com/watch?v=0bby9NQ7Ln4

Nevertheless,


Pain behaviors are well worth noting during an assessment, e.g.,

• Gait (stride length, leg swing, limp, pelvic tilt, pace, use of canes

or crutches, etc.)

• Postures (standing – swaying, leaning, shifting weight, pacing;

sitting – fidgeting, leaning, stretching out, getting up and down,

twisting, tucking leg under)

• Guarding (stiff, rigid, or awkward movements, withdrawing)

• Bracing (holding furniture, leaning on wall)

• Rubbing (pressing or massaging)

• Facial (grimacing, wincing, frowning, squinting, blinking, lip

movements, clenching)

• Sighing, groaning, grunting, moaning, gasping, exclamations


Alas, “Lay adults and even experienced physicians cannot reliably

differentiate real expressions of pain from faked expressions of pain”

Whereas even trained observers achieve only 55% accuracy,

computerized facial pattern recognition can attain 85% accuracy in

discriminating real from faked facial pain signals.

Marian S. Bartlett et al., “Automatic Decoding of Facial Movements Reveals

Deceptive Pain Expressions” Current Biology 24 (March 31, 2014): 738-743.


“There is no laboratory test or imaging technique that can

measure the patient's true versus reported experience of

sensation. The terms "magnification" and "exaggeration"

imply that we can measure true sensations and compare

these measurements with patient reports. Thus, by

definition, "symptom magnification" and "exaggerated

pain behavior" cannot be measured. Use of these terms,

therefore, should be avoided…”

Deborah E. Lechner, Sam F. Bradbury, and Laurence A. Bradley,

“Detecting Sincerity of Effort: A Summary of Methods and

Approaches” Physical Therapy 78 (1998): 867-888.


Cognitive-discriminative aspects of the pain experience

“Fear of pain and what we do about it may

be more disabling than pain itself”‒ G. Waddell et al., 1993

“Results of this meta-analysis indicate a robust, positive

association between pain-related fear and disability, which

can be classified as moderate to large in magnitude”

Emily L. Zale et al. “The Relation Between Pain-Related Fear and

Disability: A Meta-Analysis” The Journal of Pain 14 (2013)1019-

1030.


The Fear-Avoidance Model of Chronic Pain


• The Chronic Illness Problem Inventory (Romano et al., 1992)

• The Sickness Impact Profile (Bergner et al., 1981)

• The Coping Strategy Questionnaire (Lawson et al., 1990)

• The Roland and Morris Disability Questionnaire (Roland & Morris, 1983),

• The Oswestry Low Back Pain Disability Questionnaire (Fairbank et al., 1980),

• The Fear-Avoidance Beliefs Questionnaire (Waddell et al., 1993),

• The Survey of Pain Attitudes (Jensen, Karoly & Huger, 1989),

• The Pain and Impairment Relationship Scale (Riley, Ahern & Follick, 1988),

• The Pain Beliefs and Perceptions Inventory (Williams & Thorn, 1989),

• The Pain Experience Scale (Turk & Rudy, 1985),

• The Behavioral Assessment of Pain profile (Tearnan & Lewandowski, 1992),

• The Computerized Assessment of Response Bias (Conder, Allen & Cox, 1992),

• The Stress Audit (Miller at al., 1992),

• The Millon Behavioral Health Inventory (Millon et al., 1979).

Measurement Tools in Fear-Avoidance Aspects of Pain


Tampa Scale

for

Kinesiophobia

1 = strongly disagree

2 = disagree

3 = agree

4 = strongly agree


41 year old commercial/industrial

painter with chronic generalized

back pain since MVA on January 24,

2011. Has done physiotherapy,

massage therapy, acupuncture,

trigger point injections, two

epidural injections, various

medications.

Pain behaviors, 5/5 Waddell’s signs,

and flexion of elbows “hurts his

back”


Other issues in the cognitive-discriminative dimension:

• Health and fitness

• Medications taken

• Cultural background

• History of injury/illness

• Family dynamics

• Social situation

• Risk perceptions

• Lifestyle

• Sleep patterns

• Coping styles

• Mood disorders

• Fears of (re)injury/pain

• Relations with employer

• Stressors

• Beliefs

• Expectations

• Resources

• Treatments undertaken

• Legal and compensation

issues

• Relations with management

and co-workers

• History of disability


Subjective Pain Condition Objective Job Demands?


Subjective Pain Condition Objective Job Demands?

• behavioral responses to

physical assessment

• ADLs, RTW attempts,

recreational, childcare,

social functions, interests

• Assessment tools and

other observations

• Diagnoses and Pathology

• Shift duration & times

• Overtime

• Pacing (self vs. production)

• Repetition

• Forces

• Postures

• Latitude to adapt/control

• Environmental

• Supports

• Breaks

• Tools & machines

• Labour relations

• Interpersonal conflict

• Cognitive demands

• Concentration

• Safety sensitive work

• Corporate culture

• Job satisfaction and security

• Employee benefits

• Accommodated work

• Disability management


COMPARE

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CBOM Pre-conference Session - OEMACoemac.org/download/2014-Sunday/Doug Hamm_OEMAC Conference 2014_CBOM.pdf · PAIN and FITNESS TO WORK EVALUATION • Describes daily low back pain